The inFlight Guide paperback book is the Rosetta Stone of flight charts. Disc flight data contained in this guide comes from a total of 15 different flight charts and rating systems with as many as six different sources being applied to any one disc. Using multiple data sources has created the “Relative Stability Scale”. This Relative Stability Scale shows flight characteristics relative to the expected minimum and maximum range of values for all discs and are displayed as a percentage. This flight ratings scale is the easiest to understand and is very simple for players both new and old to apply to the discs in their bag and to aid in disc purchasing decisions. New and amateur players will find this guide to be a very beneficial disc resource.